Climbers heading to Rainier often ask the question, “water bottles or camelback?” Nearly every backpack sold now is “hydration system compatible” and many endurance athletes are training and competing with hydration systems. Are these systems best suited to mountaineering however?

In the past, many guides simply asked their climbers not to use hydration systems, but to carry hard sided water bottles instead. The belief was that the drawbacks of hydration systems outweighed the benefits. As hydration systems have improved to be less prone to leaking or punctures, this stance has shifted. There still are drawbacks to hydration systems, but given the right conditions, precautions, and expectations, they can be used effectively in mountaineering for a climb such as Rainier.

The main concerns we see with hydration systems are:

The hoses freeze: During midsummer climbs with high freezing levels, this doesn’t tend to be as much of a problem. On cooler climbs however, ice buildup in the hose can quickly block any water from getting through. The neoprene hose insulators are pretty ineffective, since they are thin, and it doesn’t take much ice buildup to completely block the flow. Blowing the water back through the hose after every drink can help, but still isn’t 100% effective. The best practice is to bring an empty, hard sided water bottle (even if only ½ liter capacity) that you can pour the hydration bladder into should it freeze, so that you still have access to water.

Rationing water: Climbers can only carry so much water for a climb before the weight becomes cumbersome. Typically we recommend 2-3 liters of water for a Rainier summit day. This is plenty, but requires climbers to ration it; for example, 2 liters allows a climber 1/3 of a liter of water at each break. If climbers are sipping more consistently from a hydration system, often they lose track of that rationing, and find themselves partway into a climb, with no water left. Diligent attention is the only way to solve this, and this is difficult when you can’t actually see how much water you have left.

Distractions: Trying to turn a hydration hose on and off and drink from it on the fly distracts from the climbing, the terrain, and the overall situation. When climbers are roped up and in climbing mode, each member of the team is relying on all of the others to remain vigilant to catch a fall, and to not cause a fall. A hydration hose is a distraction from this, and the solution is to either keep the hose tucked away inside the pack (where it is inaccessible) in climbing terrain, or for climbers to carefully assess the hazards of the terrain they are in at that moment, and to choose benign stretches to get their hydration.

Hard sided water bottles have been the standard in mountaineering for decades and still provide the simplest method of carrying water. They generally do not freeze, it’s easy to see how much you are drinking, and they are away in the pack while climbing. That being said, since they are tucked away in the pack, they are inaccessible, and do not allow a climber the opportunity to get a quick sip of water on a long stretch. Hydration systems may have a place in your mountaineering kit, but practice with them, have a plan, and know how to minimize the drawbacks. If in doubt, water bottles will still work fine!